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J. D. Verhoeven - One of the best experts on this subject based on the ideXlab platform.
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Damascus Steel Revisited
JOM, 2018Co-Authors: J. D. Verhoeven, A. H. Pendray, W. E. Dauksch, S. R. WagstaffAbstract:A review is given of the work we presented in the 1990s that successfully developed a technique for reproducing the surface patterns and internal microstructure of genuine Damascus Steel blades. That work showed that a key factor in making these blades was the addition of quite small levels of carbide-forming elements, notably V. Experiments are presented for blades made from slow- and fast-cooled ingots, and the results support our previous hypothesis that the internal banded microstructure results from microsegregation of V between dendrites during ingot solidification. A hypothetical model was presented for the mechanism causing the unique internal microstructure that gives rise to the surface pattern forming during the forging of the ingots from which the blades are made. This article attempts to explain the model more clearly and presents some literature data that offer support to the model. It also discusses an alternate model recently proposed by Foll.
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The continuing study of Damascus Steel: Bars from the alwar armory
JOM, 2004Co-Authors: J. D. Verhoeven, A. H. Pendray, W. E. DaukschAbstract:The authors published a paper in this journal in 1998^1 titled “The Key Role of Impurities in Ancient Damascus Steel Blades.” Because of the continued popularity of the on-line version of this paper,^2 additional experiments were conducted on some three-century old Damascus bars. The results of those experiments are reported in this paper.
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genuine Damascus Steel a type of banded microstructure in hypereutectoid Steels
Steel Research, 2002Co-Authors: J. D. VerhoevenAbstract:A brief review is given of the evolution of welded Damascus Steel and genuine Damascus Steel along with the mystery of how the pattern of genuine Damascus Steel is produced. The prior studies claiming to have either, reproduced the genuine Damascus Steel, or explained the mechanism of pattern formation, are reviewed. None of these studies have allowed modern bladesmiths to reproduce the Steel. The author and a bladesmith, Alfred Pendray, have developed a process with which Pendray can produce blades that match the microstructures of the best museum quality genuine Damascus blades. Experimental research is reviewed showing that the microstructure of this Steel is produced by an unusual type of banding that requires: (1) the presence of low levels of certain impurity elements in the hypereutectoid Steels, with V being most effective, and (2) a thermal cycling heat treatment. A main difference of this type of banding and the ubiquitous banding of hypoeutectoid Steels is point (2), the requirement of thermal cycling. A theory for the banding mechanism is presented.
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The key role of impurities in ancient Damascus Steel blades
JOM, 1998Co-Authors: J. D. Verhoeven, A. H. Pendray, W. E. DaukschAbstract:The art of producing the famous 16–18th century Damascus Steel blades found in many museums was lost long ago. Recently, however, research has established strong evidence supporting the theory that the distinct surface patterns on these blades result from a carbide-banding phenomenon produced by the microsegregation of minor amounts of carbide-forming elements present in the wootz ingots from which the blades were forged. Further, it is likely that wootz Damascus blades with damascene patterns may have been produced only from wootz ingots supplied from those regions of India having appropriate impurity-containing ore deposits.
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microsegregation and banding in hypereutectoid Steel Damascus Steel
Iron and Steelmaker, 1998Co-Authors: J. D. Verhoeven, A. H. Pendray, F Laabs, W. E. DaukschAbstract:A study is presented of carbide banding in hypereutectoid Steels containing 1.5 weight percent C. It had been postulated that, similar to the ubiquitous ferrite/pearlite banding observed in hypoeutectoid Steels, this carbide banding was produced by microsegregation of third elements present in the Fe-C alloys. It was found here that banding can be produced by the carbide forming elements, V, Mo, Nb, Cr, or Mn present at levels of only 0.03 weight percent or slightly above, or by the presence of the same levels of S or P. Microsegregation studies of these low levels of elements was successfully carried out using electron probe microanalysis (EPMA) of sulfide rich regions in the ingots. The EPMA study has found significant levels of microsegregation with these low levels of impurities and provides evidence supporting the theory that the carbide banding is produced by microsegregation. It is this carbide banding in hypereutectoid Steels that is responsible for the attractive surface patterns on the famous Damascus Steel swords of antiquity, now available mainly in museums.
A. H. Pendray - One of the best experts on this subject based on the ideXlab platform.
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Damascus Steel Revisited
JOM, 2018Co-Authors: J. D. Verhoeven, A. H. Pendray, W. E. Dauksch, S. R. WagstaffAbstract:A review is given of the work we presented in the 1990s that successfully developed a technique for reproducing the surface patterns and internal microstructure of genuine Damascus Steel blades. That work showed that a key factor in making these blades was the addition of quite small levels of carbide-forming elements, notably V. Experiments are presented for blades made from slow- and fast-cooled ingots, and the results support our previous hypothesis that the internal banded microstructure results from microsegregation of V between dendrites during ingot solidification. A hypothetical model was presented for the mechanism causing the unique internal microstructure that gives rise to the surface pattern forming during the forging of the ingots from which the blades are made. This article attempts to explain the model more clearly and presents some literature data that offer support to the model. It also discusses an alternate model recently proposed by Foll.
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The continuing study of Damascus Steel: Bars from the alwar armory
JOM, 2004Co-Authors: J. D. Verhoeven, A. H. Pendray, W. E. DaukschAbstract:The authors published a paper in this journal in 1998^1 titled “The Key Role of Impurities in Ancient Damascus Steel Blades.” Because of the continued popularity of the on-line version of this paper,^2 additional experiments were conducted on some three-century old Damascus bars. The results of those experiments are reported in this paper.
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The key role of impurities in ancient Damascus Steel blades
JOM, 1998Co-Authors: J. D. Verhoeven, A. H. Pendray, W. E. DaukschAbstract:The art of producing the famous 16–18th century Damascus Steel blades found in many museums was lost long ago. Recently, however, research has established strong evidence supporting the theory that the distinct surface patterns on these blades result from a carbide-banding phenomenon produced by the microsegregation of minor amounts of carbide-forming elements present in the wootz ingots from which the blades were forged. Further, it is likely that wootz Damascus blades with damascene patterns may have been produced only from wootz ingots supplied from those regions of India having appropriate impurity-containing ore deposits.
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microsegregation and banding in hypereutectoid Steel Damascus Steel
Iron and Steelmaker, 1998Co-Authors: J. D. Verhoeven, A. H. Pendray, F Laabs, W. E. DaukschAbstract:A study is presented of carbide banding in hypereutectoid Steels containing 1.5 weight percent C. It had been postulated that, similar to the ubiquitous ferrite/pearlite banding observed in hypoeutectoid Steels, this carbide banding was produced by microsegregation of third elements present in the Fe-C alloys. It was found here that banding can be produced by the carbide forming elements, V, Mo, Nb, Cr, or Mn present at levels of only 0.03 weight percent or slightly above, or by the presence of the same levels of S or P. Microsegregation studies of these low levels of elements was successfully carried out using electron probe microanalysis (EPMA) of sulfide rich regions in the ingots. The EPMA study has found significant levels of microsegregation with these low levels of impurities and provides evidence supporting the theory that the carbide banding is produced by microsegregation. It is this carbide banding in hypereutectoid Steels that is responsible for the attractive surface patterns on the famous Damascus Steel swords of antiquity, now available mainly in museums.
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Wootz Damascus Steel blades
Materials Characterization, 1996Co-Authors: J. D. Verhoeven, A. H. Pendray, E. D. GibsonAbstract:Wootz Damascus Steel blades contain surface patterns produced by bands of cementite particles which are generated in situ as the blades are forged from small ingots. A process for making these blades has recently been developed which involves making ingots in a gas-fired furnace followed by forging to blade shapes. This study presents a series of additional experiments which provide strong evidence that the mechanism responsible for the formation of the aligned cementite bands is similar to the mechanism that produces banded hypoeutectoid Steels. That mechanism attributes the selective formation of ferrite bands to microsegregated alloying elements. The results of this study show that the cementite bands will form in ultraclean hypereutectoid Steels (P and S levels
D A Sukhanov - One of the best experts on this subject based on the ideXlab platform.
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INFLUENCE OF PHOSPHORUS IMPURITY ON THE STRUCTURE AND NATURE OF THE DESTRUCTION OF THE GENUINE Damascus Steel
International Journal of Engineering Technologies and Management Research, 2020Co-Authors: D A SukhanovAbstract:It is established that the ancient knife blade belongs to the Eastern group of Indo-Persian Steel type genuine Damascus Steel with a pattern of "Kara-Taban", which literally means blackshiny. The methods of spectral, x-ray phase and optical analysis show that the genuine Damascus Steel is a high-purity non-alloy high-carbon Steel with a high content of phosphorus. It is revealed that phosphorus, having a high segregation coefficient of impurity contributes to the process of segregation of carbon in the process of crystallization of crucible ingots. The main physical and chemical factors influencing morphology of structure formation of genuine Damascus Steel are revealed. It is established the relationship between the structure and the nature of the destruction of the genuine Damascus Steel under impact load.
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influence of the distribution of excess carbide on the properties of genuine Damascus Steel
Materials Sciences and Applications, 2019Co-Authors: D A Sukhanov, Nataliya PlotnikovaAbstract:The methods of spectral, x-ray phase and microprobe analysis show that genuine Damascus Steel is a high-purity unalloyed high-carbon Steel with a high phosphorus content. It is shown that phosphorus in an amount of from 0.1% to 0.2%, having a high liquation coefficient, contributes to the process of segregation of carbon in interdendritic zone in the process of crystallization. Interdendritic zone formed carbon clusters, in the process of forging transform into oblong carbides cementite. The main physical and chemical factors affecting the formation of oblong carbides are revealed. The hardness of carbide layers was determined, which was about 920 HV. The hardness of the troostite matrix was amounted about 475 HV. It is established that the cutting edge of the blade knife of Damascus Steel is nothing more than a “micro-saw” consisting of parallel carbide and troostite layers. Tests are conducted on the preservation of the cutting edge sharpness of the blades knife of homogeneous structure of Steel У15А (Russian) and the layered structure of genuine Damascus Steel Ds15P (Indo-Persian). Found that with little effort cut (to 4 kg) ancient Damascus Steel (Ds15P) shows a greater number of cuts than the modern instrument Steel У15А. With an increase, force on the cutting edge from 6 kg to 12 kg carbon Tool Steel is showed a more number of cutting on the 25% than in genuine Damascus Steel. The fatigue crack propagation in the true Layered structure of Damascus Steel Ds15P occurs for a greater number of cycles than in a homogeneous structure of the Steel У15А. The blade knife of genuine Damascus Steel, in terms of fatigue reliability (survivability), has almost 2 times longer service life than the blade knife of the modern carbon tool Steel type У15А. It is proved that loss in cutting ability of a genuine Damascus Steel compensates increased the reliability (“survivability”) of the blade knife with fatigue loads.
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Nature of Angular Carbides in Damascus Steel
Metallurgist, 2017Co-Authors: D A Sukhanov, L. B. Arkhangel’skii, N. V. PlotnikovaAbstract:It is detected that in some specimens of Damascus Steel part of the excess cementite is of unusual origin, in contrast to excess phases of secondary cementite, ledeburite cementite, and primary cementite in ironcarbon alloys. It is revealed that a morphological feature of separate particles of cementite in Damascus Steel includes anomalously large excess carbides in the form of irregular octahedral and prisms. It is shown that angular carbides form within the original metastable ledeburite colonies, and therefore they are called “eutectic.” It is established that unalloyed materials of the carbide class acquire Damascus properties Steel properties during isothermal exposure on annealing, which leads to thermal separation of colonies of metastable ledeburite, to limitation of newly formed eutectic carbides, and to their subsequent coalescence. It is revealed that some sorts of Damascus Steel, being within the field of white cast iron with respect to carbon content, do not contain broken ledeburite within their structure. It is shown that the pattern of carbide inhomogeneity entirely consists of eutectic of angular carbides of non-etching triangular-prismatic morphology.
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Damascus Steel ledeburite class
Microelectronics Systems Education, 2017Co-Authors: D A Sukhanov, L B Arkhangelsky, And N V PlotnikovaAbstract:Discovered that some of blades Damascus Steel has an unusual nature of origin of the excess cementite, which different from the redundant phases of secondary cementite, cementite of ledeburite and primary cementite in iron-carbon alloys. It is revealed that the morphological features of separate particles of cementite in Damascus Steels lies in the abnormal size of excess carbides having the shape of irregular prisms. Considered three hypotheses for the formation of excess cementite in the form of faceted prismatic of excess carbides. The first hypothesis is based on thermal fission of cementite of a few isolated grains. The second hypothesis is based on the process of fragmentation cementite during deformation to the separate the pieces. The third hypothesis is based on the transformation of metastable cementite in the stable of angular eutectic carbide. It is shown that the angular carbides are formed within the original metastable colony ledeburite, so they are called "eutectic carbide". It is established that high-purity white cast iron is converted into of Damascus Steel during isothermal soaking at the annealing. It was revealed that some of blades Damascus Steel ledeburite class do not contain in its microstructure of crushed ledeburite. It is shown that the pattern of carbide heterogeneity of Damascus Steel consists entirely of angular eutectic carbides. Believe that Damascus Steel refers to non-heat-resistant Steel of ledeburite class, which have similar structural characteristics with semi-heat-resistant die Steel or heat-resistant high speed Steel, differing from them only in the nature of excess carbide phase.
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eutectic carbides in Damascus Steel ledeburite class wootz
International Research Journal of Materials Sciences and Applications, 2017Co-Authors: D A Sukhanov, L B ArkhangelskyAbstract:Considered the nature of the change of the morphology of excess carbides in Damascus Steel (Wootz), depending on the degree of supercooling of the melt, heat treatment and plastic deformation. Discovered that some of blades Damascus Steel has an unusual nature of origin of the excess cementite, which different from the redundant phases of secondary cementite, cementite of ledeburite and primary cementite in iron-carbon alloys. It is revealed that the morphological features of separate particles of cementite in Damascus Steels lies in the abnormal size of excess carbides having the shape of irregular prisms. Considered three hypotheses for the formation of excess cementite in the form of faceted prismatic of excess carbides. The first hypothesis is based on thermal fission of cementite of a few isolated grains. The second hypothesis is based on the process of fragmentation cementite during deformation to the separate the pieces. The third hypothesis is based on the transformation of metastable cementite in the stable of angular eutectic carbide. It is shown that the angular carbides are formed within the original metastable colony ledeburite, so they are called “eutectic carbide”. It is established that high-purity white cast iron is converted into of Damascus Steel during isothermal soaking at the annealing. It was revealed that some of blades Damascus Steel ledeburite class do not contain in its microstructure of crushed ledeburite. It is shown that the pattern of carbide heterogeneity of Damascus Steel consists entirely of angular eutectic carbides. Believe that Damascus Steel refers to non-heat-resistant Steel of ledeburite class, which have similar structural characteristics with semi-heat-resistant die Steel or heat-resistant high speed Steel, differing from them only in the nature of excess carbide phase.
Graham Campbell - One of the best experts on this subject based on the ideXlab platform.
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santoku chefs knife 67 layer japanese Damascus Steel
2018Co-Authors: Graham CampbellAbstract:Santoku Chefs knife - 67 layer Japanese Damascus Steel. 7 inch (175mm) Material : 67 layers high carbon Damascus Steel & 10Cr15CoMoV core Handle : Excellent red & black Pakka wood, surface polishing Hardness : 60±2 HRC Characteristics : Extremely sharp and durable Superior rust resistance Designed for low effort cutting - Easier on the muscles Optical lens processing forging process Sharpness level : the level of cutting force: 6.0-8.0 N international standards Packing: Hand wrapped, corrugated cardboard.
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Santoku Chefs knife – 67 layer Japanese Damascus Steel
2018Co-Authors: Graham CampbellAbstract:Santoku Chefs knife - 67 layer Japanese Damascus Steel. 7 inch (175mm) Material : 67 layers high carbon Damascus Steel & 10Cr15CoMoV core Handle : Excellent red & black Pakka wood, surface polishing Hardness : 60±2 HRC Characteristics : Extremely sharp and durable Superior rust resistance Designed for low effort cutting - Easier on the muscles Optical lens processing forging process Sharpness level : the level of cutting force: 6.0-8.0 N international standards Packing: Hand wrapped, corrugated cardboard.
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76 layer Damascus Japanese vg10 chefs knives
2018Co-Authors: Graham CampbellAbstract:Seriously sharp Damascus Steel - 76 layers!! Easier to use, lightweight to avoid tiring during the day. Does not get much better than these. 3 types available - Order separately or as a set for a discount : Chef Boning Paring. 20% Discount on the set of 3!
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What brand of knives do professional chefs prefer, and why?
2017Co-Authors: Graham CampbellAbstract:Oh man. Get visions of Damascus Steel exotics out of your head. Most cooks use cheap $30 knives from companies like Winco, Dexter, and Mercer. They do ...
N. V. Plotnikova - One of the best experts on this subject based on the ideXlab platform.
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Mechanism of Fe_2C Type Eutectic Carbide Formation Within Damascus Steel Structure
Metallurgist, 2018Co-Authors: D. A. Sukhanov, L. B. Arkhangel’skii, N. V. PlotnikovaAbstract:Three stages are developed for forming a Damascus Steel structure of high-purity white cast iron BU22A obtained by vacuum melting. In the first stage of the production process, a continuous of carbide sheath is formed along the boundaries of austenitic grains, which morphologically resembles ledeburite inclusions. In the second stage of the process, there is compaction and faceting of large eutectic type carbide formation. In the third stage of the production process (forging), a globular sorbite matrix is formed with faceted eutectic carbides in size from 5.0 to 20 μm distributed unevenly in the deformation direction. It is observed that the stoichiometric composition of faceted eutectic carbides is within the limits of 34 < C < 36 at.%, which corresponds to Fe_2C type ε-carbide with a hexagonal close-packed lattice. A two-stage mechanism is considered for conversion of excess secondary cementite into faceted Fe_2C type eutectic ε-carbides. It is revealed that isothermal exposure duration on heating to the eutectic temperature, is an integral part of the process of forming new excess Fe_2C type carbides with a hexagonal close-packed lattice.
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Nature of Angular Carbides in Damascus Steel
Metallurgist, 2017Co-Authors: D A Sukhanov, L. B. Arkhangel’skii, N. V. PlotnikovaAbstract:It is detected that in some specimens of Damascus Steel part of the excess cementite is of unusual origin, in contrast to excess phases of secondary cementite, ledeburite cementite, and primary cementite in ironcarbon alloys. It is revealed that a morphological feature of separate particles of cementite in Damascus Steel includes anomalously large excess carbides in the form of irregular octahedral and prisms. It is shown that angular carbides form within the original metastable ledeburite colonies, and therefore they are called “eutectic.” It is established that unalloyed materials of the carbide class acquire Damascus properties Steel properties during isothermal exposure on annealing, which leads to thermal separation of colonies of metastable ledeburite, to limitation of newly formed eutectic carbides, and to their subsequent coalescence. It is revealed that some sorts of Damascus Steel, being within the field of white cast iron with respect to carbon content, do not contain broken ledeburite within their structure. It is shown that the pattern of carbide inhomogeneity entirely consists of eutectic of angular carbides of non-etching triangular-prismatic morphology.
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Wootz: Cast Iron or Steel?
Materials Sciences and Applications, 2016Co-Authors: D. A. Sukhanov, N. V. PlotnikovaAbstract:It is shown that the excess carbide phase in Wootz is of an unusual nature origin that differs from the excess phase of secondary cementite, ledeburite and primary cementite in iron-carbon alloys. It is revealed that the morphological features of excess cementite in Wootz lie in the abnormal size of excess carbides having the shape of irregular prisms. It is discovered that the faceted angular carbides are formed within the original of metastable ledeburite, so they are called “eutectic carbides”. It was found that angular eutectic carbides in the Wootz formed during long isothermal soaking at the annealing and subsequent deformation of ledeburite structures. It is revealed that carbon takes up 2.25% in Wootz (in the region of white cast iron), while none in its structure of crushed ledeburite. It is shown that the pattern of carbide heterogeneity consists entirely of angular eutectic carbides having an irregular trigonal-prismatic morphology. It is shown that Wootz (Damascus Steel) is non-alloy tool Steel of ledeburite class, similar with structural characteristics of die Steel of ledeburite class and high-speed Steel, differing from them only in the nature of excess carbide phase.
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morphology of excess carbides Damascus Steel
Journal of Materials Science Research, 2016Co-Authors: D A Sukhanov, L B Arkhangelsky, N. V. Plotnikova, N S BelousovaAbstract:Considered the nature of changes in the morphology of carbides of the unalloyed high-carbon alloys type Damascus Steel depending on the degree of supercooling of the melt, heat treatment and plastic deformation. It is shown that iron-carbon alloy with carbon content as in white cast iron at high degrees of supercooling can crystallize as a high-carbon Steel. Considered three hypotheses for the formation of the eutectic carbides in pure iron-carbon alloys. The first hypothesis is based on the thermal process of dividing plates of secondary cementite or of ledeburite on isolated single grain. The second hypothesis is based on the deformation process of crushing of secondary cementite or of ledeburite into separate fragments (the traditional view on the formation of eutectic carbides). The third hypothesis is based on the transformation of metastable ledeburite in a stable phase of eutectic carbide prismatic morphology. Found that some types of wootz, which carbon content as in of white cast irons not is contain its structure of ledeburite. It is shown that the structure of consists entirely of the eutectic carbides prismatic morphology.
